Tuesday, March 28, 2017
New study points that two-thirds of cancers might be due to unavoidable errors associated with DNA replication, not inheritance or lifestyle
Abstract (as presented by the authors of the scientific work):
"Cancers are caused by mutations that may be inherited, induced by environmental factors, or result from DNA replication errors (R). We studied the relationship between the number of normal stem cell divisions and the risk of 17 cancer types in 69 countries throughout the world. The data revealed a strong correlation (median = 0.80) between cancer incidence and normal stem cell divisions in all countries, regardless of their environment. The major role of R mutations in cancer etiology was supported by an independent approach, based solely on cancer genome sequencing and epidemiological data, which suggested that R mutations are responsible for two-thirds of the mutations in human cancers. All of these results are consistent with epidemiological estimates of the fraction of cancers that can be prevented by changes in the environment. Moreover, they accentuate the importance of early detection and intervention to reduce deaths from the many cancers arising from unavoidable R mutations."
Covered topics (the letter size corresponds to the frequency of mentioning in the text):
Concluding paragraph (as presented by the authors of the scientific work):
"As a result of the aging of the human population, cancer is today the most common cause of death in the world (12). Primary prevention is the best way to reduce cancer deaths. Recognition of a third contributor to cancer—R mutations—does not diminish the importance of primary prevention but emphasizes that not all cancers can be prevented by avoiding environmental risk factors (Figs. 2 and 3). Fortunately, primary prevention is not the only type of prevention that exists or can be improved in the future. Secondary prevention, i.e., early detection and intervention, can also be lifesaving. For cancers in which all mutations are the result of R, secondary prevention is the only option."
Full-text access of the referenced scientific work:
Tomasetti C, Li L, Vogelstein B. Stem cell divisions, somatic mutations,
cancer etiology, and cancer prevention. Science. 2017 Mar 24;355(6331):1330-1334.
doi: 10.1126/science.aaf9011. PubMed PMID: 28336671.
Prof. Atanas G. Atanasov (Dr. habil., PhD)